# N5726: 1947 Fairchild XNQ-1

- Status: Valid registration
- Airframe: [Fairchild XNQ-1](https://openairdocs.org/model/fairchild-xnq-1) (registry code 3371808, 2 seats)
- Engine: [Lycoming R680](https://openairdocs.org/engine/lycoming-r680) (registry code 41540)
- Data sheets: [TCDS ATC 42 Textron Lycoming](https://openairdocs.org/tcds/ATC%2042%20Textron%20Lycoming) (Textron Lycoming AVCO Corporation) (OpenAirDocs)
- Serial number: 75726
- Year built: 1947
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Experimental, exhibition
- Airworthiness date: May 20, 1992
- Certificate issued: August 31, 2024
- Expires: August 31, 2031
- Mode S code: A75901
- Registered owner: [Hagerstown Aviation Museum Inc](https://openairdocs.org/faa-owner/HAGERSTOWN%20AVIATION%20MUSEUM%20INC)
- Location: [Hagerstown, MD](https://openairdocs.org/faa-place/MD/Hagerstown)
- Owner type: Corporation
- Owner's area on the map: 39.6782° N, 77.6527° W: Placed by OpenAirDocs at the center of ZIP code 21742, within about 4 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=5726
- Page: https://openairdocs.org/aircraft/N5726

From the FAA registry file of October 24, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination.

## ADs that may apply (OpenAirDocs): 5 in force

### Matched by airframe (Fairchild XNQ-1)

None in force.

### Matched by engine (Lycoming R680)

- [AD 2012-03-07](https://openairdocs.org/ad/2012-03-07): Carburetor · Lycoming Engines GO-435, GO-435-C2 (O-435-17), GO-435-C2A and 389 more. Effective Mar 27, 2012
- [AD 2004-10-14](https://openairdocs.org/ad/2004-10-14): Crankshaft gear · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 642 more. Effective Jun 25, 2004
- [AD 95-26-02](https://openairdocs.org/ad/95-26-02): Aviation Gasoline · Lycoming Engines IO-320-B1A, IO-320-B1B, IO-320-B1C and 182 more. Effective Jan 24, 1996
- [AD 90-04-06 R1](https://openairdocs.org/ad/90-04-06-R1): Propeller Governor External Oil Line · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 427 more. Effective May 28, 1991
- [AD 66-06-03](https://openairdocs.org/ad/66-06-03): Connecting Rod Assemblies · Lycoming Engines GO-435-C2 (O-435-17), GO-435-C2A, GO-435-C2A2 and 317 more. Effective Jan 16, 1969

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N5726.

## FAA accident and incident reports

None matched to N5726.

## Reports on N5726 not matched to an aircraft (4)

They name N5726, but no registry record covers the date, the aircraft registered then was built later, or the report describes another aircraft.

- [Incident 19790505025779I](https://openairdocs.org/incident/19790505025779I), May 5, 1979: Doug DC9 (N5726), Houston, TX, Minor damage. Engine shutdown due to firewarning.
- [Incident 19790315009659I](https://openairdocs.org/incident/19790315009659I), Mar 15, 1979: Doug DC9 (N5726), Dallas, TX. Flight returned due to noise in wheel well. Found gear door open
- [Incident 19780905017869I](https://openairdocs.org/incident/19780905017869I), Sep 5, 1978: Doug DC9 (N5726), Houston, TX. Flight returned due to erratic engine indications. Replaced fuel control.
- [Incident 19780401007939I](https://openairdocs.org/incident/19780401007939I), Apr 1, 1978: Doug DC9 (N5726), Texarkana, TX. Unscheduled landing for sick passenger.

## Service difficulty reports

None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model.

## STCs that may be installed (OpenAirDocs) (1)

Approved for this aircraft's airframe or engine model, in force first, then newest. The registry doesn't record which STCs an aircraft has; its records do.

### Approved for the engine (Lycoming R680)

- [STC SE04651CH](https://openairdocs.org/stc/SE04651CH): To allow use of l00R grade aviation fuel meeting Swift Fuel, LLC specification SPEC-l00R-22. Swift Fuels LLC

## Earlier aircraft with N5726

The FAA can reassign an N-number once a registration is cancelled. These aircraft carried N5726 before.

- [Cancelled 1963-02-27](https://openairdocs.org/deregistered/N5726-1963-02-27): Cessna CH-1C, S/N 45526. Owner: [Cessna Aircraft Co Military Aircraft Division](https://openairdocs.org/faa-owner/CESSNA%20AIRCRAFT%20CO%20MILITARY%20AIRCRAFT%20DIVISION), [Wichita, KS](https://openairdocs.org/faa-place/KS/Wichita)
- [Cancelled 1941-09-15](https://openairdocs.org/deregistered/N5726-1941-09-15): Monocoupe 70, S/N 105. Owner: [Morris T Cecil](https://openairdocs.org/faa-owner/MORRIS%20T%20CECIL), [Kansas City, MO](https://openairdocs.org/faa-place/MO/Kansas%20City)

## Related

- Other Fairchild XNQ-1 aircraft: https://openairdocs.org/model/fairchild-xnq-1/aircraft.md
- The Lycoming R680 engine: https://openairdocs.org/engine/lycoming-r680.md

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